My indicators stopped working on my 2004 Corolla. Both the indicator lights on the dash stay on, but the indicators won't work. When I stop the car and take the keys out both indicator lights on the dashboard start flashing. If I start the car back up, both indicator lights, on the dash, flash a few times and then stay on but the actual indicators won't work. If I turn the car off for a while (at least half hour), then it goes back to normal. Does anyone know what's wrong?